Meeting BIM Level 2 for Building Services Designers
IntroductionIn May 2011 the UK Government published the Construction Strategy that aimed to reduce waste within the construction industry by 20% by 2016. The strategy demonstrates a method of reducing problems of inaccurate or incomplete information and ambiguous results leading to additional capital costs of delivery.
The strategy centres on the Building Information Model and the use of 3D CAD modelling but there is a lot more to it than just reducing clashes through the use of computer software. The whole concept requires sharing of documentation and non-graphical data to a common data environment for all those involved to review and approve.
To meet the requirements of maturity Level 2 the guidance states that BS 1192-4 should be followed along with PAS (Publicly Available Standard) 1192. These provide the principles to be followed and plans/ models to be used as part of a Level 2 project, the key ones of which are highlighted below:
Principles1. Designers gain information from other models to create their own model.
For the Building Services Designer the majority of this information will come from the structural engineer’s model which will be integrated with their own reference data and design to create their own model.
2. Clear definition of the employers requirements.
This is the collation of design information in regard to the IT required, levels of detail, training, H&S and CDM management into a single document called the Employers Information Requirements (EIR). It is issued by the employer to all suppliers (be it a supplier of designs or equipment) and forms the basis for the BIM Execution Plan.
3. Evaluation of the proposed approach.
The capability and capacity of each supplier will be assessed at the early stages to ensure the project is achievable and so that the ideal approach to the project can be used.
4. Production of the BIM Execution Plan (BEP).
The BEP will state the roles and responsibilities of key project personnel and it will also state the standards, methods and procedures to be applied (see my previous blog Coordinating Building Design with Modern Technology).
5. Creating a single, fully accessible store of information and asset data.
The Common Data Exchange (CDE) will be used by all the specialist designers, be it electrical, mechanical or another, to enable them to be fully informed at every stage. The CDE can be a file sharing website or an open computer network.
6. Application of processes and procedures.
PAS 1192 highlights the key documents that will give guidance to all designers and coordinators through the design development. Amongst these is the Construction Project Information Xchange (CPIx) that will be used assess designers capability and capacity to delivery designs.
7. Development of information models.
To achieve this various types of software and databases can be adopted to analyse the design and to facilitate the sharing of information between different designers. This may include AutoCAD Revit, IES, Hevacomp or Amtech software.
Plans/ModelsUnder a maturity Level 2 project there will are a variety of documents, plans and models that the Building Services Designer may come across during his work. These include:
Common Data Environment (CDE).
This is the core of the delivery process and provides the means by which sharing and collaboration can be completed. For a Building Services Designer this means developing the design internally to a point where it ‘Issued for Sharing’ (or stage S0) and then reacting to comments/ coordination with other project partners. The information in the CDE can be used by estimators, planners and, once complete, by the Facilities Manager as well.
Master Information Delivery Plan (MDIP).
This is the lead document stating when design information is to be issued and by whom. It also states the required formats and procedures to be used by the task delivery teams.
Task Information Delivery Plan (TIDP).
The TIDPs are written and used by task delivery teams (i.e. Mechanical Engineers) and by bringing all of these together the MIDP is formed. As with the MIDP the TIDP will state the information deliverables including format, date and responsibilities.
Project Information Model (PIM).
This is the all-encompassing model that develops from the design stage, through construction and onto the handover of the delivered project. It consists of documentation, graphical and non-graphical information that form the completed design.
GuidanceFurther guidance can be obtained from:
PAS 1192-2: 2013 – Specification for information management for the capital/ delivery phase of construction projects using building information modelling (BSI).
BS 1192 – 4: 2014 – Collaborative production of information (BSI).
BIM Protocol – Standard Protocol for use in projects using Building Information Models (CIC/ CIM Pro).